Abstract
When engaging in visual search in daily life, people tend to adopt suboptimal attentional control strategies. What factors underlie such suboptimality? Are there ways to promote better strategies? To address these questions, Irons and Leber (2018) designed the Adaptive Choice Visual Search (ACVS) to measure visual search strategies. In the ACVS, the optimal strategy is to search through the less numerous of two color subsets. Initial work has shown two possible causes of suboptimality, including 1) participants do not know what the optimal strategy is, and 2) they are not provided sufficient time to implement the strategy. However, previous efforts to independently investigate these possibilities have not yielded consistent results. For instance, providing additional time (via a display “preview” manipulation) has only sometimes boosted optimality. It is possible that both knowledge and preview interact, such that instructions on the optimal strategy have the greatest effect when a preview is provided. Here, we directly tested this hypothesis by manipulating both factors. In Experiments 1 and 2, we tested the preview effect with durations from 250 to 2000 ms. In both experiments, participants were randomly assigned to either an Instruction Group or a Control Group. Results revealed that in the control group, the effect of preview on optimality reached a plateau around 500 ms, as longer durations did not offer extra help. In the instruction group, however, the impact of the preview was observed well after the control-group's plateau. Overall, a significant interaction between the effects of preview and instruction on optimality was observed. These results are consistent with our prediction that the utility of knowledge increases with greater opportunity for implementation. Nevertheless, sufficient time for previewing and instruction of optimal strategy did not guarantee optimal behavior, indicating that other factors like cognitive effort may also influence people’s behaviors.